Freud tracked the psyche along the paths of sleep, following the “royal road” of dreams. For the ancient Greeks, too, the psyche was revealed in sleep, not through the semiotics of dreams but through the peculiar state of being we occupy while asleep. As a “borderland between living and not living” (as Aristotle puts it), sleep offered unique access to the psukhē , that element within the self unassimilable to waking consciousness. This paper examines how Greek philosophers theorized the sleep state and the somnolent psukhē , focusing on Heraclitus, Plato, and Aristotle. Each of the three attempts to reclaim sleep for waking life and to join the sleeping soul to the philosophical self. But that attempt never fully succeeds. Instead sleep consistently emerges as a philosophical blindspot, a state that—unlike dreams—cannot be spoken by philosophy's logos nor fully illuminated by philosophical analysis.